This test is highly specific for large effusions but may miss smaller amounts of fluid, which are better detected using the Bulge Sign . 2. Obstetric Ballottement
Use one hand to firmly stroke downward from the mid-thigh toward the kneecap. This "milks" fluid out of the suprapatellar pouch and into the space behind the patella. ballottement
(from the French ballotter , meaning "to toss about") is a medical physical examination technique used to detect floating objects within a fluid-filled cavity. It is most commonly applied in orthopedics to check for knee swelling, in obstetrics to assess pregnancy, and in general medicine to evaluate abdominal organs. 1. Patellar Ballottement (Knee Effusion Test) This test is highly specific for large effusions
This is the most frequent use of the term. It is used to identify a "floating" kneecap, which indicates a moderate-to-large accumulation of fluid (effusion) within the knee joint. This "milks" fluid out of the suprapatellar pouch
Performed by applying a sharp tap to the abdominal wall to feel the fetus move away and return. 3. Abdominal Ballottement
In pregnancy, ballottement is a "probable sign" used to detect the fetus as it floats in amniotic fluid.
The clinician inserts two fingers into the vagina and gives a sharp upward tap against the lower segment of the uterus. If the fetus is present and not yet engaged in the pelvis, it will float upward and then fall back, tapping against the clinician’s fingers.